Method and apparatus for controlling an input device

1. An information processing device comprising: a capacitance variation detection unit configured to detect an operation input to each of a plurality of key regions as a capacitance variation amount of a capacitive element, the key region being provided on a sheet-like operation member, the capacitive element being provided in association with each of the key regions, the capacitance variation amount being dependent on a change in a distance between the key region and the capacitive element; and an input state determination unit configured to: determine whether an input state of the key region is an ON state based on the detected capacitance variation amount, the ON state being a state in which the operation input to the key region is decided to be valid, determine an end of the ON state based on a differential delta value of the capacitance variation amount; prevent the input state of the key region determined to be the end of the ON state from being determined to be the ON state again until the capacitance variation amount becomes less than or equal to a first threshold after the end of the ON state is determined; wherein the input state of the key region is determined to be the ON state when the capacitance variation amount is more than or equal to a second threshold, wherein the first threshold is smaller than the second threshold; wherein the end of the ON state is determined at a time when a magnitude of the differential delta value of the capacitance variation amount is more than or equal to a magnitude of a first differential threshold; and wherein the first differential threshold has a sign indicating that a distance between the key region and the capacitive element becomes large.

2. The information processing device according to claim 1 , wherein the input state determination unit further determines that an input state of the key region is the ON state when the differential delta value of the capacitance variation amount is more than or equal to a second differential threshold regardless of a magnitude of the capacitance variation amount.

3. An information processing device comprising: a capacitance variation detection unit configured to detect an operation input to each of a plurality of key regions as a capacitance variation amount of a capacitive element, the key region being provided on a sheet-like operation member, the capacitive element being provided in association with each of the key regions, the capacitance variation amount being dependent on a change in a distance between the key region and the capacitive element; and an input state determination unit configured to: determine whether an input state of the key region is an ON state based on the detected capacitance variation amount, the ON state being a state in which the operation input to the key region is decided to be valid; wherein the input state of the key region is the ON state when a differential delta value of the capacitance variation amount is more than or equal to a first differential threshold regardless of a magnitude of the capacitance variation amount, or when the capacitance variation amount is more than or equal to a first threshold, wherein the first differential threshold and the first threshold are set in a manner that different types of operation input performed on the key region by a user are distinguishable from each other, wherein the first differential threshold is set depending on a rate of change in the distance between the key region and the capacitive element when a user presses the key region, and wherein the first threshold is set depending on an amount of change in the distance between the key region and the capacitive element when a user presses and holds the key region; determine a time at which a magnitude of the differential delta value of the capacitance variation amount is more than or equal to a magnitude of a second differential threshold; and determine that the time at which the magnitude of the differential delta value of the capacitance variation amount is more than or equal to the magnitude of the second differential threshold corresponds to a time at which the ON state has ended, prevent the input state of the key region determined to be the end of the ON state from being determined to be the ON state again until the capacitance variation amount becomes less than or equal to the first threshold after the end of the ON state is determined wherein the second differential threshold has a sign indicating that a distance between the key region and the capacitive element becomes large.

4. The information processing device according to claim 3 , wherein the input state determination unit, when one of the key regions is provided with a plurality of the capacitive elements, compares the differential delta value of the capacitance variation amount of each of the capacitive elements with the first differential threshold, and determines that the input state of the key region is the ON state when any one of the differential delta values of the capacitance variation amount is more than or equal to the first differential threshold.

5. A non-transitory computer readable storage medium having computer readable instructions stored thereon that, when executed, cause a processor of a computer to execute the functions of: detecting an operation input to each of a plurality of key regions as a capacitance variation amount of a capacitive element, the key region being provided on a sheet-like operation member, the capacitive element being provided in association with each of the key regions, the capacitance variation amount being dependent on a change in a distance between the key region and the capacitive element; determining whether an input state of the key region is an ON state based on the detected capacitance variation amount, the ON state being a state in which the operation input to the key region is decided to be valid; determining an end of the ON state based on a differential delta value of the capacitance variation amount; preventing the input state of the key region determined to be the end of the ON state from being determined to be the ON state again until the capacitance variation amount becomes less than or equal to a first threshold after the end of the ON state is determined; wherein the input state of the key region is determined to be the ON state when the capacitance variation amount is more than or equal to a second threshold; wherein the first threshold is smaller than the second threshold; wherein the end of the ON state is determined at a time when a magnitude of the differential delta value of the capacitance variation amount is more than or equal to a magnitude of a first differential threshold; and wherein the first differential threshold has a sign indicating that a distance between the key region and the capacitive element becomes large.